Stem cells may preclude hip replacements

British physicians say some patients with osteonecrosis who need hip replacements could be treated with stem cells from their own bone marrow. The procedure, developed by Doug Dunlop of Southampton General Hospital in England, involves mixing the stem cells with cleaned, crushed bone from another patient who has had his own hip replaced and using it to fill the hole made after damaged tissue removed from the joint, The Daily Telegraph reported. The new stem cell therapy could prevent the need for hip replacements due to osteonecrosis, a condition where poor blood supply causes significant bone damage leading to severe arthritis, Dunlop said. The stem cells send chemical signals to blood vessels and it's hoped the new vessels in the hip would supply nutrients to improve bone strength, Dunlop explained. Oesteoarthrits, caused by wear and tear of the bone, results from the temporary or permanent loss of blood flow to bones. This causes osteonecrosis -- or the bones to "die" -- and ultimately severe arthritis, but if osteonecrosis occurs at the bone joint, it can cause it to collapse and the only option is a hip replacement, Dunlop said.